Let me respond to the very intelligent Shogun post, as this kind of math is in fact the way to determine what is better.

I'm at level 20 (well less actually) now. And as he correctly states its 21-40 killz per quest. Lets take 35 (cause of extra exp you get during the quest) as a resonable figure. Do I quest or not?

The facts that you have left out are mana regen per second and dps and mob HP. These 35 kills are of mobs of about 500HP each. Lightning level 3 is about 1 damage per mana. Thus to kill one mob you need 500 mana, lets assume you need 1000 mana for resists and what not. Lightning can be cast every 5 seconds or faster assuming instant pop mobs. Mana pool is about 400. Level 3 lightning is about 60 mana. (this is from memory so I could be wrong). From experice I would say that 400 mana regens in less then one minute. Lets say 10 mana per second, its fairly fast. 25 X 10 mana per second is 250 mana a second or sufficient mana to do 125 damage per second or to kill a mob every 4 seconds ...

35 mobs X 4 seconds is 2.2 minutes to get the same exp as a quest ... To get 26 its 1 hour (actually its longer with looting time and trade skillz time).

Ok does a quest take less then or more then one hour to complte 6 times?

Of course as levels go up more mobs are needed but then again how much does your mana regen go up and your damage per mana go up? If you are generating enough to kill a mob every 2 seconds well ...

At any rate when I hit level 30 Ill go over the figures again.